SW (FINANCE) I PLC

(LEGAL ENTITY IDENTIFIER: 549300BHN1HB5BNG2R96)

Publication of Final Terms

21 January 2026

The following final terms are available for viewing:

Final Terms dated 19 January 2026 for SW (FINANCE) I PLC's £200,000,000 Sub-Class A21 5.750% Fixed Rate Class A Guaranteed Bonds due 19 November 2030 (to be consolidated and form a single series with the existing Series 15 £375,000,000 Sub-Class A21 5.750% Fixed Rate Class A Guaranteed Bonds due 19 November 2030 issued on 19 November 2025) issued under its £10,000,000,000 Multicurrency Programme for the issuance of Guaranteed Bonds (the "Programme").

The Final Terms contain the final terms of the Bonds and must be read in conjunction with the prospectus dated 10 November 2025 (the "Prospectus") relating to the Programme, which constitutes a base prospectus for the purposes of the UK Prospectus Regulation.

To view the Final Terms, please paste the following URL into the address bar of your browser:

http://www.rns-pdf.londonstockexchange.com/rns/8422P_1-2026-1-21.pdf

A copy of the Final Terms and the Prospectus to which they relate have been submitted to the National Storage Mechanism and are or will shortly be available for inspection at:

https://data.fca.org.uk/#/nsm/nationalstoragemechanism

For further information, please contact Stuart Ledger (Group CFO) at:

Address:       Southern House, Yeoman Road, Worthing, BN13 3NX, United Kingdom

Tel:               01903 272 611

Email:           stuart.ledger@southernwater.co.uk

DISCLAIMER - INTENDED ADDRESSEES

Please note that the information contained in the Final Terms (when read together with the information in the Prospectus) may be addressed to and/or targeted at persons who are residents of particular countries (specified in the Prospectus) only and is not intended for use and should not be relied upon by any person outside these countries and/or to whom the offer contained in the Final Terms and the Prospectus is not addressed. The Final Terms and the Prospectus are not intended for use in the United States and are not addressed to or targeted at U.S persons and should not be relied upon by any U.S. persons. Prior to relying on the information contained in the Final Terms and the Prospectus, you must ascertain from the Prospectus whether or not you are one of the intended addressees of the information contained therein.

Your right to access this service is conditional upon complying with the above requirement.